Production system gerneral-purpose cell

ABSTRACT

In a production system general-purpose cell for general-purpose use in processing and transportation of a received workpiece in a production system of processing and delivering the workpiece, the production system general-purpose cell includes a base unit having a planar shape of quadrangle and supporting at least a robot for use in transportation of the workpiece such that the robot is movable on the planar area of quadrangle, a parts supply unit for supplying parts of the workpiece to the robot supported by the base unit, and a processing area extending outside the base unit. The robot supported by the base unit having a motion range set in a range from inside to outside the base unit in a form including at least part of the processing area.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/557,602 filed Jul. 25, 2012, which is a continuation application ofU.S. patent application Ser. No. 12/035,706 filed on Feb. 22, 2008, nowU.S. Pat. No. 8,327,531 issued Dec. 11, 2012, which claims priority toJapanese Patent Application No. 2007-057798 filed on Mar. 7, 2007, allof which are hereby expressly incorporated by reference herein in theirentireties.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a production system general-purposecell and a production system having a line layout using thegeneral-purpose cell.

2. Related Art

Regarding compact electrical products, electronic products, and thelike, small batches of a variety of products have increasingly beenproduced and product cycles have increasingly been reduced in recentyears.

Production lines producing the electrical products, electronic products,and the like tend to involve frequent rearrangement of line layouts inaccordance with products to be produced.

Since it takes much time and cost to change such production lines in achangeover from production of one product to production of anotherproduct, cell production by human hands is used in many cases.

However, automatization of production lines is desired even in suchcases from the viewpoints of product quality and production stability.

To address this issue, there has been proposed a system such as thatdisclosed in Japanese Patent No. 3336068, a first related art example.

In this system, a production system together with a conveyor thattransports a workpiece placed on a pallet, which is a holding medium fora workpiece, is configured as assembling cells, as aimed at reduction oflosses in time and costs relevant to a line configuration.

That is, this system allows selective supply of parts from a pluralityof parts supply devices, which are separately disposed, to each dividedcell and causes the cell itself to have a function of machiningworkpieces suitably for a variety of products to thereby reduce lossesin time and costs and promote automatization.

There has been proposed another system such as that disclosed inJapanese Patent No. 3673117, a second related art example.

In this system, a robot placed on a base of a cell (robot unit) that isadjacent to a cell in question with a working bench interposedtherebetween is provided, and an assembling tool of the robot as well asparts of a workpiece are transported to the cell in question so that therobot itself attaches and detaches the assembling tool and performsmachining operations for the workpiece.

Providing a transportation means that carries in an assembling toolrequired for of each cell together with parts of a workpiece and carriesout the assembling tool after use together with the workpiece machinedby the robot, as mentioned just above, further promotes theaforementioned automatization.

On the other hand, there has been still another system such as thatdisclosed in JP-A-2006-43844, a third related art example, in view of adisadvantage of providing the foregoing robot on the base.

In this system, robots are supported in a state of ceiling-hung by usingsupporting members provided separately from assembling work benches, andparts supply units that supply parts to movable ranges of the robots aredisposed facing the robots.

Supporting the robots in a state of ceiling-hung as mentioned just aboveallows space on the assembling work benches (bases) to be widelysecured, and in turn the degree of freedom relevant to assemblingoperations on the assembling work benches to be maintained higher.

As described above, various systems have been proposed so as to reducelosses in time and costs required for changes of a line configurationand further promote automatization.

However, from the viewpoints of general versatility as the foregoingcell or the degree of freedom in a line layout, there is still room forimprovement.

For example, in the case of a cell or a system described in the firstrelated art example, pallets for holding the aforementioned workpiecesneed to be prepared by type for various types of workpieces (products)that are production objects.

In implementing the system, a large amount of pallets are thereforeneeded.

Time and costs required for the design and manufacture cannot beignored.

In addition, this system is one of transporting the pallets by aconveyor.

Therefore, the system involves a disadvantage in that the productionquantity and production capacity of a line are limited by thetransportation capacity of the conveyor itself.

In the case of a system described in the second related art example, theforegoing conveyor and the like are unnecessary.

However, the system has a structure in which a robot is placed on a baseconstituting a cell.

Therefore, restrictions on the operation area required for processing ofa workpiece including attachment and detachment of an assembling tool bya robot itself and further restrictions on the size of a traytransported by the foregoing transportation means cannot be ignored.

If a large operation area and a large tray size are secured, upsizing ofthe entire production system including a cell cannot be avoided.

In a system described in the third related art example, although spaceon the assembling work benches can be widely secured, the parts supplyunits are configured to face the assembling work benches.

The degree of freedom of a line layout is limited of itself.

After all, it is difficult to reduce losses in time and costs requiredfor changes in a line configuration.

SUMMARY

An advantage of the invention is to provide a production systemgeneral-purpose cell and a production system using the general-purposecell with which the degree of freedom of a line layout can be maintainedhigh because of high general versatility as the cell, and in turn lossesin time and costs in changes of a line layout can be reduced morepreferably.

In a production system general-purpose cell according to a first aspectof the invention, as a production system general-purpose cell forgeneral-purpose use in processing and transportation of a receivedworkpiece in a production system of processing and delivering theworkpiece, the production system general-purpose cell includes: a baseunit having a planar shape of quadrangle and supporting at least a robotfor use in transportation of the workpiece such that the robot ismovable on the planar area of quadrangle; a parts supply unit forsupplying parts of the workpiece to the robot supported by the baseunit; and a processing area extending outside the base unit.

The robot supported by the base unit has a motion range set in a rangefrom inside to outside the base unit in a form including at least partof the processing area.

With this structure as a production system general-purpose cell, onegeneral-purpose cell is configured as a set of minimum elements that arerequired for processing of a workpiece as the cell for a productionsystem, such as a base unit, a parts supply unit, and a processing area.

This, as a matter of course, increases the degree of freedom, that is,the general versatility of task assignment for a cell in question.

It enables achievement of various production functions required for aproduction system only by placing the cells configured in this way insequence. That is, the degree of freedom of a line layout in configuringa production system can be maintained high.

In the general-purpose cell, since the foregoing processing area extendsoutside the base unit and the motion range of the robot provided in thebase unit is set in a range from the inside to the outside the base unitin a form including part of the processing area, the application rangeof the processing area expands of itself.

Including the use, e.g., as an area for manual operations, theprocessing area can be used for various applications as follows:

(a) the use as an area for placing a specific processing machine thatperforms required processing for the transported workpiece,

(b) the use as an area where a robot itself performs required processingfor a workpiece, and the like.

In these cases, parts required for processing of a workpiece aresupplied for each cell through the foregoing parts supply unit, andtherefore tasks or production functions assigned to the cell in questionas a unit are completed for each cell.

In addition, since the planar shape of the base unit itself isquadrangular, the degree of freedom of placing cells in sequence in sucha manner as to mutually share the motion range of a robot is maintainedhigh.

The degree of design freedom in arranging the foregoing parts supplyunit and processing area to the base unit is also maintained high.

Further, the foregoing robot is movably supported by the base unit in aplanar area forming a quadrangle.

This allows effective utilization of an area constituting the base unit,and eliminates unnecessary upsizing of the general-purpose cell.

Note that in the general-purpose cell as described above, the processingarea constituting the general-purpose cell may be configured as aseparate, replaceable body extending outside the base unit.

In this case, the effect of suppressing transmittance of vibrationbetween the processing area and the base unit can be expected.

In this production system general-purpose cell, such a structure may beemployed that a material feed and removal area for use in at least oneof feed of the workpiece to a cell in question and removal of theworkpiece from the cell in question further extends outside the baseunit in a manner of being included in a motion range of the robot.

This production system general-purpose cell enables transportation ofworkpieces between cells to be performed through the foregoing materialfeed and removal areas provided in a motion range of the robot 60.

This facilitates feed of workpieces to the general-purpose cell 100 andremoval of the workpieces from the general-purpose cell by a so-calledbucket-brigade method.

In this production system general-purpose cell, it is preferable that aside wall standing upright to the base unit be provided separately fromthe processing area in the base unit, and the robot be supported by thebase unit in such a manner that the robot protrudes from the side wall.

As with this production system general-purpose cell, as one example ofsuch a supporting manner that the foregoing robot is movably supportedby the base unit in a planar area of quadrangle, the robot is supportedin such a manner that the robot protrudes from the side wall configuredin this way in the base unit.

This facilitates securing an area required for the base unit, andparticularly securing a motion range of a robot on a side of theforegoing processing area.

In this production system general-purpose cell, it is preferable thatthe processing area extend like a table from the base unit with a stepat a position higher than the base unit, and the parts supply unit havea tray feeder that transports a parts tray with parts of the workpiececarried thereon from a back surface side of the side wall through thebase unit to a lower portion of the processing area structured like atable.

With this production system general-purpose cell, parts carried on theparts tray to be supplied can be transported through the base unit to alower portion of the processing area, that is, a position lower than theprocessing area by the tray feeder.

This allows operations such as operations of picking up the parts by therobot protruding from the side wall of the base unit and operations oftransporting the picked-up parts to the processing area by the robot tobe carried out more smoothly, and also allows the whole of thetable-like processing area to be utilized more effectively.

On the other hand, in this production system general-purpose cell, it ispreferable that a ceiling supported through a support be provided in anupper portion of the base unit, and the robot be supported by the baseunit in a manner of being hung from the ceiling.

As with this production system general-purpose cell, as another exampleof such a supporting manner that the foregoing robot is movablysupported by the base unit in a planar area of quadrangle, the robot issupported in such a manner that the robot is hung from a ceiling.

This allows the motion range of the robot to cover a wide rangeincluding the whole area below the ceiling.

In particular, an area constituting the base unit is utilized moreeffectively.

In this production system general-purpose cell, it is particularlypreferable to employ as the foregoing robot a selective complianceassembly robot arm (SCARA) type robot including first and second armseach having a motion area of one of a circle and a circular arc, thesecond arm being passable through a position overlapping the first arm.

With this production system general-purpose cell, the robot has firstand second arms that basically have motion areas of a circle or acircular arc and each pass mutually overlapping positions.

This enables the motion range of the entire robot to be basically in acircle or a circular arc and efficiently cover the required area in themotion range of the robot set inside the circle or the circular arc,that is, from inside to the outside the base unit with the collaborationof the first and second arms.

In this production system general-purpose cell, it is more preferablethat the parts supply unit supply a part for the workpiece to a vicinityof the processing area.

If the robot is supported in such a manner that it is hung from theceiling, there is basically no portion to block the supply of parts bythe parts supply unit.

Accordingly, the degree of freedom in arrangement of the parts supplyunit is maintained high as a matter of course.

As with this production system general-purpose cell, the parts supplyunit may be one that can transport parts to a vicinity of the processingarea.

Even with this, operations of picking up appropriate parts by the robotand operations of transporting the picked-up parts to the processingarea by the robot are carried out smoothly.

In addition, in this case, the motion range of the robot broadly coversthe transportation area of the parts supply unit that transports partsto the base unit.

This therefore allows reduction of the frequency of operations requiredfor supplying parts by means of the foregoing parts supply unit tray,e.g., by upsizing the parts supply unit itself.

On the other hand, in this production system general-purpose cell, it isalso preferable to employ a structure in which the cell itself thatincludes the parts supply unit disposed in the base unit and theprocessing area has a planar shape of quadrangle.

With this production system general-purpose cell, the quadrangularplanar shape of the cell itself including the parts supply unit and theprocessing area enables, even in the case of using a plurality ofgeneral-purpose cells, uniform decision of arrangement of the pluralityof general-purpose cells.

This in turn facilitates design of a line layout as the productionsystem.

On the other hand, in this production system general-purpose cell, whena specific processing machine for processing the workpiece is disposedin the processing area, functions of the cell may be set such that therobot carries out operations of:

a. transportation of the workpiece to the processing area;

b. picking up of a part supplied through the parts supply unit;

c. integration of the picked-up part into the workpiece; and

d. delivering the workpiece processed by the processing machine.

This production system general-purpose cell embodies a manner of using aprocessing area exemplified in the aforementioned (a).

That is, in this case, processing of the workpiece is specificallyperformed by the processing machine placed in the processing area.

Therefore, even if a production system is configured in a sequence ofthe cells, the robot disposed in the base unit only has to repeatedlycarry out operations of the aforementioned a to d.

Standardization of the general-purpose cell mentioned above is thuspromoted, and the general versatility is maintained very high.

In this production system general-purpose cell, functions of the cellmay be set such that the robot carries out operations of:

a. transportation of the workpiece to the processing area;

b. picking up of a part supplied through the parts supply unit;

c. integration of the picked-up part into the workpiece;

d. processing of the workpiece having the part integrated therein in theprocessing area; and

e. delivering the workpiece processed in the processing area.

This production system general-purpose cell embodies a manner of using aprocessing area exemplified in the aforementioned (b).

In this case, the above operations a to e, that is, all operations to becarried out for the cell in question are carried out by means of therobot disposed in the base unit.

Therefore, if a production system is configured in a sequence of thecells, the content of processing for the robot to carry out needs to beset (programmed) for each cell.

However, if the set content is registered into a storage device such asthe data base in advance, changes, e.g., in line configuration can behandled by updating the set content for each cell.

The required general versatility is maintained in this case.

Further, in this production system general-purpose cell, when anautomatic tool changer with which the robot automatically replaces ahand of itself with a new one is placed, functions of the cell may beset such that the robot carries out operations of:

a. picking up of a part supplied through the parts supply unit;

b. integration of the picked-up part into the workpiece;

c. processing of the workpiece having the part integrated therein;

d. delivering the processed workpiece; and

e. automatic replacement of a robot hand as needed for the operations ofa to d by means of the automatic tool changer.

This production system general-purpose cell embodies a still anothermanner of using a processing area.

In this case, the above operations a to e, that is, all operations to becarried out for the cell in question are basically carried out by meansof the robot disposed in the base unit.

Particularly in this case, automatic replacement of a robot hand, asneeded, by means of the automatic tool changer provided in theprocessing area is carried out as the operation of the above e togetherwith other operations, and therefore more kinds of operations can behandled.

In this case, when a production system is configured in a sequence ofthe above cells, the content of processing for the robot to carry outneeds to be set (programmed) for each cell.

However, the general versatility required as the cell in question ispreferably maintained by registering in advance the set content into astorage device and the like.

In a production system using a general-purpose cell according to asecond aspect of the invention, such a structure is employed that aplurality of the production system general-purpose cells as describedabove arranged in such a manner that the cells adjacent to each othershare part of the motion range of the robot.

It has been described above that a production system general-purposecell, which is used here, itself is configured as a set of minimumelements that are required for processing of a workpiece as the cell fora production system, such as a base unit, a parts supply unit, and aprocessing area, and the degree of freedom, that is, the generalversatility of task assignment for the cell is greatly increased.

Therefore, with a production system according to the second aspect ofthe invention in which a plurality of production system general-purposecells as described above arranged in such a manner that the cellsadjacent to each other share part of the motion range of the robot,pallets, conveyer belts, and the like for transporting a workpiece are,of course, unnecessary, and a high degree of freedom of a line layoutitself is maintained.

This therefore enables achievement of a very free line layout, such as alinear arrangement of the cells and an arrangement of a line bent in themiddle by ±90° to form an “L” shape or a “U” shape in accordance with aspace for placing this production system, and the like, and what ismore, at low costs.

In this production system, it is preferable to further include aworkpiece automatic transportation unit that automatically transports aworkpiece so as to enable, between such the cells that motion ranges ofrobots in the cells are mutually unreachable, transferring and receivingof the workpiece within the motion ranges of the robots.

This production system allows a more wide variety of line layouts suchas making part or the whole of a line in a parallel manner using theforegoing workpiece automatic transportation units, in addition to theline layouts described above, and also facilitates adjustment of theline speed and adjustment of the transportation timing in accordancewith processing contents of workpieces between cells.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a perspective view illustrating an entire perspectiveconfiguration of first embodiment of a production system general-purposecell according to the invention.

FIG. 2 is a side view illustrating a side configuration of a robotemployed for the general-purpose cell of the embodiment.

FIG. 3 is a plan view illustrating an entire planar configuration of thegeneral-purpose cell of the embodiment.

FIG. 4 is a plan view illustrating a planar configuration of thegeneral-purpose cell 100 with a focus on a parts supply unit 20 employedfor the general-purpose cell of the embodiment.

FIG. 5 is a block diagram illustrating an electrical construction of thegeneral-purpose cell of the embodiment.

FIGS. 6A to 6D are plan views illustrating operation examples of thegeneral-purpose cell of the embodiment.

FIG. 7 is a plan view illustrating an example of a line configuration asa production system that uses a plurality of general-purpose cells ofthe embodiment.

FIG. 8 is a block diagram illustrating an electrical construction as theproduction system.

FIG. 9 is a plan view illustrating another example of the lineconfiguration as the production system that uses a plurality ofgeneral-purpose cells of the embodiment.

FIG. 10 is a plan view illustrating a still another example of the lineconfiguration as the production system that uses a plurality ofgeneral-purpose cells of the embodiment.

FIG. 11 is a perspective view illustrating an entire perspectiveconfiguration of a second embodiment of a production systemgeneral-purpose cell according to the invention.

FIG. 12A illustrates a side configuration of a robot employed for thegeneral-purpose cell of the second embodiment, and FIGS. 12B to 12D arebottom views each schematically illustrating one example of motion modesand motion ranges seen from the below.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Embodiments of the invention will be described.

First Embodiment

Description will be given below on a first embodiment that implements aproduction system general-purpose cell and a production system using thegeneral-purpose cell according to the invention, with reference to thedrawings.

FIG. 1 illustrates an entire perspective configuration of a productionsystem general-purpose cell according to the first embodiment.

As illustrated in FIG. 1, a general-purpose cell 100 includes a baseunit 10, which supports a robot 60, positioned at the center, and aparts supply unit 20 and a processing area 30 both disposed in a rowalong the direction of the X axis of three dimensional coordinates addedin the figure.

In the present embodiment, the base unit 10, the parts supply unit 20,and the processing area 30 constituting the general-purpose cell 100 areall made of metal having rigidity and are mutually suitably connected,and can be moved and placed in blocks of cell by using casters 41 andfoot jacks 42 attached onto a bottom surface 40 of the general-purposecell 100.

In other words, the general-purpose cell 100 can be moved in anydirection on the floor surface by using the casters 41 on the bottomsurface 40, and can also be fixed to a desired position by using thefoot jacks 42 on the bottom surface 40.

Additionally, in the embodiment, the planar shape of the base unit 10and the general-purpose cell 100 itself are quadrangular (rectangular).

Such shapes facilitate design of a line layout for a production systemusing a plurality of general-purpose cells 100.

In the general-purpose cell 100, a cabinet 43 is disposed in a lowerportion of the base unit 10.

In the cabinet 43, a control device, which supervises and controls theforegoing robot 60 and other units of the general-purpose cell 100, andthe like are contained.

Here, the specific configuration of the above base unit 10 will be firstdescribed.

As illustrated in FIG. 1, in the base unit 10, a side wall 11 standingupright to the base unit 10 is disposed on the side of the boundary withthe parts supply unit 20, and the aforementioned robot (SCARA type robotin this example) 60 is supported in such a form that the robot 60protrudes from the side wall 11 toward the processing area 30.

That is, the robot 60 is supported by the base unit 10, accuratelyagainst the side wall 11, in such a manner as to be movable in the X, Y,and Z axis directions of three dimensional coordinates on a region 12having a planar shape of quadrangle, which is a top surface of the baseunit 10.

In the embodiment, a material supply area 50 a serving as a unit ofsupplying a workpiece to a cell 100 in question and a material removalarea 50 b serving as a unit of removing the workpiece from the cell 100in question extend from side plates 13 a and 13 b, respectively,disposed on both sides of the region 12 to both sides (Y direction) ofthe base unit 10 in such a manner so as to be within the motion range ofthe robot 60 described above.

FIG. 2 illustrates a side configuration of the robot 60, and furtherdetails of the configuration and functions of the robot 60 are describedin the following with reference to FIG. 2.

As illustrated in FIG. 2, the robot 60 is supported by a base 61extending from the side wall 11 mentioned above into the X direction inthe figure, and has a first arm 63 and a second arm 65 that areseparately rotatable in a horizontal direction (X-Y direction in thefigure) through a first shaft 62 and a second shaft 64, respectively.

In an edge of the second arm 65 among these components, a third shaft 66extending in the same direction (Z direction in the figure) as those ofthe first and second shafts 62 and 64 is further provided. In the thirdshaft 66, a head unit 67, which is rotatable in a horizontal directionindependently from the turn of the second arm 65, is disposed in aportion positioned below the second arm 65.

The head unit 67 has, in an edge thereof, a tool fixture 68.

With an arbitrary tool attached to the tool fixture 68, the head unit 67can freely expand and contract between a position where it is containedin the third shaft 66 (the shortest position) and a position where itextends for a distance L1 indicated by a dotted line in FIG. 2 (thelongest position).

Note that the first shaft 62 rotates right and left around a center lineC1 of a first motor M1, which is disposed in the base 61, by the firstmotor M1 to cause the first arm 63 with a base portion connected to thefirst shaft 62 to turn.

The rotation angle of the first shaft 62, that is, the turning angle ofthe first arm 63 is monitored through a first encoder Em1 disposed, likethe first motor M1, in the base 61.

The second shaft 64 causes the second arm 65 to turn.

That is, the second shaft 64 is connected to an edge of the first arm63, and when forces are applied to the second shaft 64 by a second motorM2 disposed in the second arm 65 so that the second shaft 64 rotatesright and left around a center line C2 of the second motor M2, thereaction forces act on the second arm 65 itself to cause the second arm65 to turn.

The rotation angle of the second shaft 64, that is, the turning angle ofthe second arm 65 is monitored through a second encoder Em2 disposed,like the second motor M2, in the second arm 65.

The head unit 67 that rotates, expands and contracts in the third shaft66 rotates right and left around a center line C3 of the third shaft 66by a third motor M3 disposed in the second arm 65, and the rotationangle is monitored through a third encoder Em3 disposed, like the thirdmotor M3, in the second arm 65.

On the other hand, regarding expansion and contraction of the head unit67, the degree of the expansion and contraction is controlled by anelevating motor M4 disposed in the second arm 65, and the controlleddegree is monitored through an elevating encoder Em4 disposed, like theelevating motor M4, in the second arm 65.

Signal lines of control signals and monitor signals of these motors andencoders disposed in the second arm 65 are collected through a flexiblewiring tube 63 t into the base 61, and then are coupled together withsignal lines of the first motor M1 and the first encoder Em1 from thebase 61 to the corresponding terminals of a control device contained inthe cabinet 43.

FIG. 3 illustrates a planar configuration of the general-purpose cell100 including a parts tray Tr, which is omitted in FIG. 1 forconvenience.

In the general-purpose cell 100, such a motion range of the robot 60 isset to one illustrated as a region Ra (indicated by an alternate longand two short dashes line) in FIG. 3, that is, a range from the insideto the outside the base unit 10 in a form including part of theprocessing area 30.

In this way, picking up of parts from the parts tray Tr supportedthrough the parts supply unit 20 to be described below and otheroperations such as transportation (movement) of a workpiece between thematerial supply area 50 a, the material removal area 50 b, and theprocessing area 30 can be easily achieved with high general versatility.

Like FIG. 3, FIG. 4 illustrates the planar configuration of thegeneral-purpose cell 100.

FIG. 4 particularly illustrates it with a focus on the planarconfiguration of the parts supply unit 20 mentioned above.

In the following, the configuration and functions of the parts supplyunit 20, and further its relation with the processing area 30 will bedescribed in detail with reference to FIG. 4.

As illustrated in FIG. 4, the parts supply unit 20 includes a pair ofrails 22 a and 22 b laid on the region 12 having a quadrangular planarshape, which is the top surface of the base unit 10, and a tray feeder21 that automatically transports the parts tray Tr having a pocket P forcarrying parts in the X direction in the figure through the rails 22 aand 22 b.

Here, inside each of the pair of rails 22 a and 22 b, ball screws (notillustrated) are arranged over the whole rail, and nails 23 a and 23 band nails 24 a and 24 b threadably engaged with the ball screws beforeand after the parts tray Tr.

That is, the tray feeder 21 automatically transports, as needed, theparts tray Tr together with the nails 23 a and 23 b and nails 24 a and24 b threadably engaged with the ball screws through the rotation of theball screws in the X direction in the figure.

Note that, in the tray feeder 21, the rotary drive of such ball screwsare carried out by first and second shuttle motors MSa and MSb disposedin a base portion of the tray feeder 21.

The amounts of rotation of the first and second shuttle motors MSa andMSb, that is, the amount of movement of the parts tray Tr is monitoredthrough first and second shuttle encoders ESa and Esb disposed, like thefirst and second shuttle motors MSa and MSb, in the base portion of thetray feeder 21.

Signal lines of the shuttle motors and shuttle encoders, like the signallines of motors and encoders of the robot 60, are coupled to thecorresponding terminals of a control device contained in the cabinet 43.

As illustrated in FIG. 1 referenced above, the pair of rails 22 a and 22b are laid via an opening 11 a of the side wall 11, which is formed in aplanar shape of “U” to maintain high rigidity.

That is, the pair of rails 22 a and 22 b are laid from the back surfaceside of the side wall 11 through the base unit 10 to a lower portion ofthe processing area 30 structured like a table.

The parts tray Tr carrying thereon parts needed on the back surface sideof the side wall 11, which is indicated by an alternate long and twoshort dashes line in FIG. 4, is automatically transported to a desiredposition in such a manner as indicated by an arrow F1 in FIG. 4 by thetray feeder 21, as needed.

In this way, the parts tray Tr can be transported to a position lowerthan the processing area 30 structured like a table.

This causes operations of picking up parts by the robot 60, operationsof transporting the picked-up parts to the processing area 30 by therobot 60, and the like to be smoothly carried out.

This also allows the transportation positions of the parts tray Tr(supply positions of the tray feeder 21) to be sequentially adjusted soas to supplement the limited motion range of the robot 60 whileeffectively utilizing the whole of the table-like processing area 30 atall times.

On the other hand, the processing area 30 extends in a table shape fromthe base unit 10 with a step at a position higher than the base unit 10,accurately the region 12 having a quadrangular planar shape, which isthe top surface of the base unit 10, as illustrated in FIG. 1 referencedabove.

In addition, the processing area 30 has a configuration where atable-like stage 31 is supported by legs 32.

Particularly in the embodiment, placed on the stage 31 is a processingmachine 70 that performs processing specifically assigned for each cellfor a workpiece.

The processing machine 70 itself may be configured arbitrarily, e.g.,employing a dedicated robot.

However, at least the processing machine 70 as mentioned above is placedon the stage 31 in the processing area 30.

As a result, the general-purpose cell 100 only has to basicallytransport a workpiece and pick up its parts through the robot 60.

This promotes standardization of the operations of the general-purposecell 100.

Note that a workpiece holding area 71 for holding a transportedworkpiece is provided in the processing machine 70 as illustrated inFIG. 3.

In the workpiece holding area 71, a chuck (not illustrated) for holdinga workpiece is provided.

The chuck is opened and closed by the drive of a switching valve BL1provided in the workpiece holding area 71.

Through this chuck, whether or not a workpiece is held is monitoredthrough a sensor U1.

Like the above signal lines of motors and encoders of the robot 60 andfurther the above signal line of shuttle motors and shuttle encoders ofthe tray feeder 21, signal lines of these valve and sensor are coupledto the corresponding terminals of a control device contained in theaforementioned cabinet 43.

Here, referring to FIG. 5, the electrical construction of thegeneral-purpose cell 100 will be described with a central focus on theaforementioned control device.

As illustrated in FIG. 5, the control device contained in the cabinet 43basically includes a controller 110 that is made of a computer andsupervises and controls each unit, and various driver circuits andinterface circuits bus-coupled to the controller 110.

Among these units, the controller 110 is a unit that carries out aprogram stored on a ROM 112 through a CPU 111 while taking in theaforementioned various monitor signals, thereby generating andoutputting control signals for each actuator concerned.

Note that operation results and the like in generating the abovetaken-in monitor signals and the above control signals are temporarilystored on a RAM 113, which is a data memory.

A communication interface (IF) 114 is a unit that communicates with acentral controller serving as a main control device and othergeneral-purpose cells in making a desired line layout by arranging aplurality of general-purpose cells 100 as a production system.

Based on information through such the communication IF 114, timelyadjustment with other general-purpose cells is achieved.

For such convenience in communications, each general-purpose cell isprovided with a unique identifier (ID) for the controller 110 in asystem.

On the other hand, various driver circuits and interface circuits thatare bus-coupled to the controller 110 are circuits as described in thefollowing.

First, a first motor driver 101 is a circuit that drives the first motorM1 provided in the base 61 of the robot 60 by drive signals DM1generated based on a control command CM1 from the controller 110.

The first motor driver 101 takes in signals monitored through the firstencoder Em1 provided, like the first motor M1, in the base 61, that is,signals S1 representing a rotation angle of the first arm 63corresponding to the amount of drive of the first motor M1, and alsocarries out operations of transmitting the taken-in monitor signals S1to the controller 110.

A second motor driver 102 is a circuit that drives the second motor M2provided in the second arm 65 of the robot 60 by drive signals DM2generated based on a control command CM2 from the controller 110.

The second motor driver 102 takes in signals monitored through thesecond encoder Em2 provided, like the second motor M2, in the second arm65, that is, signals S2 representing a rotation angle of the second arm65 corresponding to the amount of drive of the second motor M2, and alsocarries out operations of transmitting the taken-in monitor signals S2to the controller 110.

A third motor driver 103 is a circuit that drives the third motor M3provided, like other motors, in the second arm 65 of the robot 60 bydrive signals DM3 generated based on a control command CM3 from thecontroller 110.

The third motor driver 103 takes in signals monitored through the thirdencoder Em3 provided in the second arm 65, that is, signals S3representing a rotation angle of the head unit 67 corresponding to theamount of drive of the third motor M3, and also carries out operationsof transmitting the taken-in monitor signals S3 to the controller 110.

An elevating motor driver 104 is a circuit that drives the elevatingmotor M4 provided, like other motors, in the second arm 65 of the robot60 by drive signals DM4 generated based on a control command CM4 fromthe controller 110.

The elevating motor driver 104 takes in signals monitored through theelevating encoder Em4 provided in the second arm 65, that is, signals S4representing the degree of the expansion and contraction of the headunit 67 corresponding to the amount of drive of the elevating motor M4,and also carries out operations of transmitting the taken-in monitorsignals S4 to the controller 110.

A first shuttle motor driver 105 is a circuit that drives the firstshuttle motor MSa provided in the aforementioned tray feeder 21 by drivesignals DMSa generated based on a control command CMSa from thecontroller 110.

The first shuttle motor driver 105 takes in signals monitored throughthe first shuttle encoder ESa provided, like other motors, in the trayfeeder 21, that is, signals SSa representing the movement amount of theparts tray Tr corresponding to the amount of drive of the first shuttlemotor MSa, and also carries out operations of transmitting the taken-inmonitor signals SSa to the controller 110.

A second shuttle motor driver 106 is a circuit that drives the secondshuttle motor MSb provided in the tray feeder 21 by drive signals DMSbgenerated based on a control command CMSb from the controller 110.

The second shuttle motor driver 106 takes in signals monitored throughthe second shuttle encoder ESb provided, like other motors, in the trayfeeder 21, that is, signals SSb representing the movement amount of theparts tray Tr corresponding to the amount of drive of the second shuttlemotor MSb, and also carries out operations of transmitting the taken-inmonitor signals SSb to the controller 110.

A valve driver 107 is a circuit that drives the switching valve BL1provided in the workpiece holding area 71 of the aforementionedprocessing machine 70 based on a control command CMBc from thecontroller 110.

Note that in the embodiment such a type of chuck that opens and closeson the basis of the presence and absence of compressed air supplied isexpected for use as a chuck to hold a workpiece in the workpiece holdingarea 71.

The foregoing switching valve BL1 is designed as such a valve thatswitches and controls the presence and absence of compressed air basedon the drive of the valve driver 107.

An external input/output (I/O) IF 108 is a circuit that is basicallycoupled with peripheral devices such as a teaching pendant and apersonal computer and mediates various information sent and receivedbetween the peripheral devices and the controller 110.

In the embodiment, in addition, information monitored through the sensorU1 in the workpiece holding area 71, that is, information SBcrepresenting whether or not a workpiece is held is taken in through thechuck, and operations of outputting the taken-in monitor information SBcto the controller 110 are carried out through the external I/O IF 108.

Further, in the embodiment, the processing machine 70 described abovefunctions as one of peripheral devices and its controller is coupled tothe external I/O IF 108.

Synchronizing in operations between the controller 110 and theprocessing machine 70, and the like are designed to be performed throughthe external I/O IF 108.

FIGS. 6A to 6D illustrate operation examples of an individual cell ofthe general-purpose cell 100 having a configuration as described above.

In the following, one example of operations carried out using thegeneral-purpose cell 100 will be described with reference to FIGS. 6A to6D.

In the embodiment, as a result of placing the specifically assignedprocessing machine 70 on the stage 31 in the processing area 30, thegeneral-purpose cell 100 only has to basically transport a workpiece andpick up its parts through the robot 60, as described above.

This promotes standardization of the operations of the general-purposecell 100.

Note that the following operations of such the general-purpose cell 100should all be carried out in collaboration with the control describedabove of the control device.

That is, if a workpiece W is now supplied to the aforementioned materialsupply area 50 a as illustrated in FIG. 6A, the general-purpose cell 100moves the robot 60 to the material supply area 50 a, and grasps thesupplied workpiece W by using an appropriate tool for workpiecetransportation that is attached to the robot 60.

The general-purpose cell 100 that has thus grasped the workpiece W bymeans of the robot 60 then transports the workpiece W to the processingarea 30 while grasping the workpiece W, and sets the transportedworkpiece W to the workpiece holding area 71 of the processing machine70 in a manner illustrated in FIG. 6B.

After finishing the setting of the workpiece W to the workpiece holdingarea 71, the general-purpose cell 100 picks up parts T carried on thepockets P of the parts tray Tr using the robot 60 in a mannerillustrated in FIG. 6C.

Note that the parts tray Tr on which the parts T used for processing ofthe workpiece W are carried has already been transported to apredetermined position by the aforementioned tray feeder 21 (FIG. 4)prior to the process illustrated in FIG. 6A.

At this point, the parts T picked up by the robot 60 in this way arealso integrated into the workpiece W set in the workpiece holding area71 by the robot 60.

After the parts T have been incorporated into the workpiece W in thisway, specific processing by the processing machine 70 is performed inaccordance with a direction from the controller 110 of thegeneral-purpose cell 100.

When the processing by the processing machine 70 is completed,information on the completion is sent to the controller 110 through theprocessing machine 70.

With this, the general-purpose cell 100 determines that the processingby the processing machine 70 has been completed, and releases theholding (setting) of the workpiece W.

The general-purpose cell 100 that has determined the completion of theprocessing by the processing machine 70 in this way grasps the processedworkpiece W in the workpiece holding area 71 using the robot 60 again,and transports this processed workpiece W to the material removal area50 b in a manner illustrated in FIG. 6D.

Thus a series of operations is completed.

While operations as described above are repeatedly carried out, theposition of the parts tray Tr is sequentially shifted forward (in adirection of the processing area 30) by a distance corresponding to aninterval of carrying the parts T by the aforementioned tray feeder 21(FIG. 4) every time one row of the parts T carried on the parts tray Trhas been picked up from the head of the tray Tr by the robot 60.

If it is determined that integration of all the parts T carried on theparts tray Tr has finished, then the parts tray Tr is returned to theposition in the base portion indicated by an alternate long and twoshort dashes line in FIG. 4 by the tray feeder 21, preparing forreplenishment of the parts T to the tray.

FIG. 7 illustrates one example of a production system that uses aplurality of general-purpose cells 100 as described above (fivegeneral-purpose cells 100A to 100E in this example).

A configuration example as such a production system and its possibilitywill be described below.

As illustrated in FIG. 7, this production system employs a line layoutin which the general-purpose cells 100 (100A to 100E) are arranged in asingle row in the Y direction in the figure from a workpiece carrying-indevice 81 to a workpiece carrying-out device 82.

That is, in this case, the plurality of cells 100A to 100E are arrangedin such a manner that the cells adjacent to each other share part of themotion range of the robot 60 (60A to 60E).

As a portion where the cells adjacent to each other share the motionrange of the robot 60, either a portion to constitute the aforementionedmaterial supply area 50 a or a portion to constitute the aforementionedmaterial removal area 50 b is used.

Specifically, for example, a common area 50 a or 50 b interposed betweenthe general-purpose cells 100A and 100B is used as the material removalarea 50 b for the cell 100A while being used as the material supply area50 a for the cell 100B.

FIG. 8 schematically illustrates an electrical construction in the caseof a production system (production line) using a plurality ofgeneral-purpose cells 100 in this way.

As illustrated in FIG. 8, operation timing and the like are actuallysynchronized among the plurality of general-purpose cells 100 (100A to100 n (n: natural number)) through communication with the centralcontroller 120, which is not illustrated in FIG. 7.

In addition, in the central controller 120 illustrated in FIG. 8, a hostcomputer 121 is a unit that supervises and controls the entireproduction system, and a data base 122 is a unit in which e.g.,production management information for each of various production objectsand control data and control programs of each general-purpose cell 100required when a production line is changed are stored. An input-outputdevice 123 mainly includes a key board, a display, a printer, and thelike.

Through these key board, display, printer, and the like, inputtingcontrol information to the host computer 121, displaying the operationstate of the entire system, printing, and the like are performed.

The communication IF 124 is a unit that mediates communication betweenthe central controller 120 and each general-purpose cell 100, and iscoupled through a bus line to the communication IF 114 disposed in thecontroller 110 of each general-purpose cell 100 illustrated in FIG. 5referenced above.

A production system exemplified in FIG. 7 is electrically coupled inthis manner such that communication is possible.

This allows processing and transportation for a workpiece to beperformed while avoiding interference among the robots 60A to 60E undersupervision and control by the foregoing central controller 120,specifically in the following manner.

In other words, if carrying-in of a workpiece for the leadinggeneral-purpose cell 100A starts by the workpiece carrying-in device 81,the carried-in workpiece is transported into a stage (processing stage)31, accurately a workpiece holding area of the processing machine (notillustrated) placed on the stage 31, by the robot 60A as described abovein the general-purpose cell 100A.

In a manner described above, after incorporation of parts into theworkpiece and processing by a processing machine are performed, theprocessed workpiece is transported into the material removal area 50 b(the material supply area 50 a for the cell 100B) by the robot 60A.

Note that processes relevant to carrying in a workpiece by means of theworkpiece carrying-in device 81 for the general-purpose cell 100A thathas completed the transportation of a workpiece to the material removalarea 50 b, transporting the workpiece by the general-purpose cell 100A,and processing are repeatedly performed until throwing of apredetermined number of workpieces into the processes is completed.

On the other hand, in the general-purpose cell 100B where a workpiecehas been carried into (supplied to) the material supply area 50 a, asdescribed above, the carried-in workpiece is transported to the stage 31by the robot 60B, and after processing is performed by the specificprocessing machine, the processed workpiece is transported to thematerial removal area 50 b (the material supply area 50 a for the cell100C) by the robot 60B.

Such processes in the cell 100B are also repeatedly performed untilcarrying-in of workpieces to the material feed area 50 b is completed.

Subsequently, the same processes are performed in the general-purposecells 100C to 10E.

In particular, workpieces transported from the cell 100E at the finalstage to the workpiece carrying-out device 82 are sequentially containedas completed products or semi-completed products into storage rack (notillustrated) and the like.

In a production system using a general-purpose cell according to theembodiment as described above, pallets, conveyer belts, and the like fortransporting a workpiece are, of course, unnecessary, and a high degreeof freedom of a line layout itself is maintained in accordance witharrangement of the material removal area 50 b and the material supplyarea 50 a as the common area interposed between cells adjacent to eachother.

FIGS. 9 and 10 illustrate other production line examples that supportsuch a high degree of freedom of a line layout as the production system.

FIG. 9 illustrates an example in which an array of a plurality ofgeneral-purpose cells 100 (six general-purpose cells 100A to 100F inthis example) is bent at two points in the middle by 90° to form a linelayout in a “U” shape.

In other words, two cells, the general-purpose cell 100C and thegeneral-purpose cell 100E, are designed to have a cell configurationwhere the stage (processing stage) 31 is disposed beside a base unit,and the material removal area 50 b or the material supply area 50 a asthe common area of the cells adjacent to each other interposed in aportion where the stage 31 should have been disposed.

In this case, basic functions as each of the general-purpose cells 100Ato 100F are the same as those of the aforementioned general-purpose cell100.

Such a simple change of a cell configuration allows a line layout ofthis “U” shape as well as an “L” shape, and further a more complexshape.

Note that operations of each cell carried out under supervision andcontrol by the central controller as the production system from theworkpiece carrying-in device 81 to the workpiece carrying-out device 82are basically the same as those exemplified in the FIG. 7 referencedabove, and duplicate explanations are omitted here.

FIG. 10 illustrates an example further including workpiece automatictransportation units 131 and 132 in arranging a plurality ofgeneral-purpose cells 100 (nine general-purpose cells 100A to 100I inthis case).

The workpiece automatic transportation units 131 and 132 eachautomatically transport a workpiece so as to enable, between such cellsthat motion ranges of robots in the cells are mutually unreachable,transferring and receiving of the workpiece within the motion ranges ofthe robots.

In this example, motion ranges of the robots 60B and 60E and the robots60F and 60G do not cover the distances between the general-purpose cell100B and general-purpose cell 100E and between the general-purpose cell100F and general-purpose cell 100G, respectively.

In an ordinary way, transferring and receiving a workpiece between suchcells is impossible.

However, providing the workpiece automatic transportation units 131 and132 between cells allows a workpiece to be transferred and receivedbetween the cells concerned.

This in turn allows construction of a parallel line as illustrated inFIG. 10 with which workpieces can be separately transferred.

Therefore, it becomes possible to select a workpiece transportation pathwith a very high degree of flexibility including the workpiece automatictransportation units 131 and 132, and it becomes easy to adjust the linespeed and the transportation timing in accordance with the processingcontents of workpieces between cells.

Note that since the workpiece automatic transportation units 131 and 132have constant transportation amounts (movement amounts) of workpieces,complex control and the like are not needed.

However, their configurations themselves may be equivalent, e.g., tothose of the tray feeder 21 illustrated in FIG. 4 referenced above.

As described above, with a production system general-purpose cell and aproduction system using the general-purpose cell according to theembodiment, the effects listed in the following are obtained.

(1) One production system general-purpose cell 100 is configured as aset of minimum elements that are required for processing of a workpieceas a cell for a production system, such as the foregoing base unit 10,the parts supply unit 20, and the processing area 30.

This, as a matter of course, increases the degree of freedom, that is,the general versatility of task assignment for each cell 100.

It enables achievement of various production functions required for aproduction system only by placing the cells 100 configured in this wayin sequence.

That is, the degree of freedom of a line layout in configuring aproduction system can be maintained high.

Further, the foregoing robot 60 is movably supported by the base unit 10in a planar area forming a quadrangle.

This allows effective utilization of an area constituting the base unit10, and eliminates unnecessary upsizing of the general-purpose cell 100.

(2) In the foregoing general-purpose cell 100, the application range ofthe processing area 30 expands since the processing area 30 extendsoutside the base unit 10 and the motion range of the robot 60 providedin the base unit 10 is set in a range from the inside to the outside thebase unit 10 in a form including part of the processing area 30.

In addition, although the processing area 30 may be used, e.g., as anarea for manual operations, the specific processing machine 70 is placedon the stage 31 constituting the processing area 30 in the foregoinggeneral-purpose cell 100, significantly promoting standardization as acell as well as automatization.

In other words, in this case, the robot 60 only has to basically carryout operations such as transporting a workpiece to the processing area30 (the workpiece holding area 71 of the processing machine 70), pickingup parts supplied through the parts supply unit 20, integrating thepicked-up parts into a workpiece, and delivering the workpiece processedby the processing machine 70.

(3) The material feed and removal areas 50 a and 50 b used for at leastone of feed of workpieces to the general-purpose cell 100 and removal ofthe workpieces from the general-purpose cell 100 further extend outsidethe foregoing base unit 10 in such a manner as to be included in amotion range of the robot 60.

This enables transportation of workpieces between cells to be performedthrough the material feed and removal areas 50 a and 50 b provided in amotion range of the robot 60, facilitating feed of workpieces to thegeneral-purpose cell 100 and removal of the workpieces from thegeneral-purpose cell 100 by a so-called bucket-brigade method.

(4) The foregoing base unit 10 is provided with a side wall 11 standingupright to the base unit 10, and the foregoing robot 60 is supported bythe base unit 10 in such a manner that the robot 60 protrudes on theregion 12 having a quadrangular planar shape of the base unit 10.

This facilitates securing an area required for the base unit 10, andparticularly securing a motion range of a robot on a side of theforegoing processing area 30.

(5) The foregoing processing area 30 is configured such that theforegoing stage 31 extends in a table shape from the base unit 10 with astep at a position higher than the base unit 10, specifically the region12, which has a quadrangular planar shape, of the base unit 10.

The foregoing parts supply unit 20 includes the tray feeder 21 thattransports the parts tray Tr carrying workpiece parts from the backsurface side of the side wall 11 through the base unit 10 to a lowerportion of the table-like processing area 30.

In other words, parts carried on the parts tray Tr to be supplied aretransported through the base unit 10 to a lower portion of theprocessing area 30, that is, a position lower than the processing area30 by the tray feeder 21.

This allows operations such as operations of picking up the parts by therobot 60 protruding from the side wall 11 of the base unit 10 andoperations of transporting the picked-up parts to the processing area 30by the robot 60 to be carried out more smoothly, and also allows thewhole of the table-like processing area 30 to be utilized moreeffectively.

In this case, the parts tray Tr can be sequentially moved to a lowerportion of the processing area 30 (stage 31) in accordance with themotion range of the robot 60.

This enables employment of a larger or longer tray as the parts tray Tr.

(6) As the basic configuration of the foregoing general-purpose cell100, the planar shape of the cell itself including the parts supply unit20 and the processing area 30 as well as the base unit 10 isquadrangular.

The quadrangular planar shape of the cell itself including the partssupply unit 20 and the processing area 30 in this way enables, even inthe case of using a plurality of general-purpose cells 100, uniformdecision of arrangement of the general-purpose cell 100.

This in turn facilitates design of a line layout as the productionsystem.

However, as in the general-purpose cell 100C and the general-purposecell 100E exemplified in FIG. 9, the processing area 30 can extendbeside the base unit 10.

In this case, a line layout in such a manner that a line is bent in themiddle by ±90° as illustrated in FIG. 9 becomes possible.

(7) Regarding a production system using a general-purpose cell, aplurality of general-purpose cells 100 are arranged in such a mannerthat the cells adjacent to each other share part of the motion range ofthe robot 60.

Thus, pallets, conveyer belts, and the like for transporting a workpieceare, of course, unnecessary, and a high degree of freedom of a linelayout itself is maintained.

This therefore enables achievement of a very free line layout, such as alinear arrangement of the cells as exemplified in FIG. 7 and anarrangement of a line bent in the middle by ±90° to form an “L” shape ora “U” shape as exemplified in FIG. 9 in accordance with a space forplacing this production system, and the like.

(8) In constructing a production system, the workpiece automatictransportation units 131 and 132 are further included that eachautomatically transport a workpiece to enable, between such cells thatmotion ranges of robots in the cells are mutually unreachable in theordinary way, transferring and receiving of the workpiece within themotion ranges of the robots.

This allows a more wide variety of line layouts such as making part orthe whole of a line in a parallel manner using the workpiece automatictransportation units 131 and 132, in addition to the line layoutsdescribed above, and also facilitates adjustment of the line speed andadjustment of the transportation timing in accordance with processingcontents of workpieces between cells.

Second Embodiment

FIG. 11 illustrates a perspective configuration of a second embodimentof a production system general-purpose cell according to the invention.

In the second embodiment, a form of supporting a robot to a base unit ischanged from the above-mentioned form of a robot protruding from a sidewall to a form of so-called ceiling-hung.

A specific configuration of the general-purpose cell will be describedbelow focusing on differences from the first embodiment described above.

As illustrated in FIG. 11, a general-purpose cell 200 according to thepresent embodiment includes a base unit 10 a, which supports a robot 90,positioned at the center, and a parts supply unit 20 a and a processingarea 30 a both disposed along the direction of the X axis of threedimensional coordinates added in the figure.

In the embodiment, as in the first embodiment, the base unit 10 a, theparts supply unit 20 a, and the processing area 30 a constituting thegeneral-purpose cell 200 are all made of metal having rigidity and aremutually suitably connected, and can be moved and placed in blocks ofcell by using casters 41 and foot jacks 42 attached onto a bottomsurface 40 of the general-purpose cell 200.

Additionally, in the embodiment, as in the first embodiment, the planarshapes of the base unit 10 a and the general-purpose cell 200 itself arequadrangular (rectangular).

Such shapes facilitate a line layout design for a production systemusing a plurality of general-purpose cells 200.

Just as in the first embodiment, in the general-purpose cell 200, acabinet 43 is disposed in a lower portion of the base unit 10 a, and acontrol device, which supervises and controls the foregoing robot 90 andother units of the general-purpose cell 200, and the like are containedin the cabinet 43.

Here, the specific configuration of the above base unit 10 a will firstbe described.

As illustrated in FIG. 11, in the base unit 10 a, a ceiling 11 rsupported by supports 11 p is disposed, and the aforementioned robot(SCARA type robot in this example, as in the example of the firstembodiment) 90 is supported by the base unit 10 a in such a form thatthe robot 90 is hung from the ceiling 11 r.

That is, the robot 90 is supported by the base unit 10 a, accurately theceiling 11 r, in such a manner as to be movable in the X, Y, and Z axisdirections of three dimensional coordinates on a region 12 having aquadrangular planar shape, which is a top surface of the base unit 10 a.

In the embodiment, a material supply area 50 a serving as a unit ofsupplying a workpiece to the cell 200 and a material removal area 50 bserving as a unit of removing the workpiece from the cell 200 extendfrom side plates 13 a and 13 b disposed on both sides of the region 12to both sides (Y direction) of the base unit 10 a, respectively, in sucha manner as to be within the motion range of the robot 90 describedabove.

FIG. 12A illustrates a side configuration of the robot 90, and FIGS. 12Bto 12D illustrate motion modes and motion ranges seen from the below.

Further details of the configuration and functions of the robot 90 aredescribed in the following with reference to FIGS. 12A to 12D.

As illustrated in FIG. 12A, the robot 90 is supported by a first shaft91 disposed passing through the ceiling 11 r and extending from theceiling 11 r into the vertical direction, and has first and second arms92 and 94 that are separately turnable in a horizontal direction throughthe first shaft 91 and a second shaft 93, respectively.

In an edge of the second arm 94 among these components, a third shaft 95extending in the same direction (vertical direction) as those of thefirst and second shafts 91 and 93 is further provided. In the thirdshaft 95, a head unit 96, which is rotatable in a horizontal directionindependently from the turn of the second arm 94, is disposed in aportion positioned below the second arm 94.

The head unit 96 has, in an edge thereof, a tool fixture 97.

With an arbitrary tool attached to the tool fixture 97, the head unit 96can freely expand and contract between a position where it is containedin the third shaft 95 (the shortest position) and a position where itextends for a distance L1 indicated by a dotted line in FIG. 12A (thelongest position).

Note that the first shaft 91 rotates right and left around a center lineC1 of the a first motor M1, which is provided inside the first shaft 91,by the first motor M1 to cause the first arm 92 with an edge thereofconnected to the first shaft 91 to turn.

The rotation angle of the first shaft 91, that is, the turning angle ofthe first arm 92 is monitored through a first encoder Em1 disposed, likethe first motor M1, in the first shaft 91.

The second shaft 93 rotates right and left around a center line C2 ofthe a second motor M2, which is provided inside the second shaft 93, bythe second motor M2 to cause the second arm 94 with an edge thereofconnected to the second shaft 93 to turn.

The rotation angle of the second shaft 93, that is, the turning angle ofthe second arm 94 is monitored through a second encoder Em2 disposed,like the second motor M2, in the second shaft 93.

The head unit 96 that rotates, expands and contracts in the third shaft95 rotates right and left around a center line C3 of the third shaft 95by a third motor M3 disposed in the second arm 94, and the rotationangle is monitored through a third encoder Em3 disposed, like the thirdmotor M3, in the second arm 94.

On the other hand, regarding expansion and contraction of the head unit96, the degree of the expansion and contraction is controlled by anelevating motor M4 disposed in the second arm 94, and the controlleddegree is monitored through an elevating encoder Em4 disposed, like theelevating motor M4, in the second arm 94.

Note that signal lines of control signals and monitor signals of thesemotors and encoders are coupled to the corresponding terminals of acontrol device contained in the cabinet 43, just as in the firstembodiment.

Regarding the robot 90, the first and second arms 92 and 94 are set inthe same length so that their motion areas are basically circular andthey can each pass the overlapping positions.

With the collaboration of these arms, motions in the whole of a circulararea illustrated as a motion range Ra1 in FIG. 12B are covered.

That is, FIG. 12B illustrates a state of the robot 90, as seen from thebelow, in a so-called original attitude with the first and second arms92 and 94 overlapping each other in a “U” shape.

In the embodiment, in this state, the second arm 94 is turnableclockwise and counterclockwise about a point P1 by 225°, and similarlythe first arm 92 is independently turnable about the center point inFIG. 12B to cause the point P1 to swing clockwise and counterclockwiseby 225°.

In this respect, FIG. 12C illustrates the turning locus, that is, amotion range Rat of the first and second arms 92 and 94.

If the first arm 92 causes the second arm 94 to swing clockwise by 225°,the second arm 94 can turn clockwise and counterclockwise about thepoint P1 and a point P2 by 225°.

Likewise, FIG. 12D illustrates the turning locus, that is, a motionrange Ra3 of the first and second arms 92 and 94.

If the first arm 92 caused the second arm 94 to swing counterclockwiseby 225°, the second arm 94 can turn clockwise and counterclockwise aboutthe point P1 and a point P3 by 225°.

The combined turning loci are illustrated in FIG. 12B.

After all, as described above, with the collaboration of the first andsecond arms 92 and 94, motions in the whole of a circular areaillustrated as a motion range Ra1 in FIG. 12B are covered.

Note that, in the embodiment, the head unit 96 is turnable clockwise andcounterclockwise by 225° independently from the second arm 94.

With such motions of the robot 90, all dead angles at least on the baseunit 10 a, accurately on the region 12 of a quadrangular planar shape,are eliminated.

Therefore, regarding the general-purpose cell 200 illustrated in FIG.11, transportation of the workpiece and picking up of parts carried onthe parts tray (not illustrated) that is transported by the tray feeder21 of the parts supply unit 20 a, which have been described above, arecarried out more smoothly.

Note that, in the general-purpose cell 200 illustrated in FIG. 11, anoperating panel OP having a keyboard and a display for monitoring (allnot illustrated) is provided on the top of the ceiling 11 r of the baseunit 10 a.

Through this operating panel OP, various settings required for each cellcan be made.

A status indicator PL placed on the operating panel OP is a device thatinforms an operator and the like of the operating status and otherstatuses of the general-purpose cell 200, as occasion demands, withluminescent units of different colors.

The aforementioned other items described with reference to FIGS. 3 to 6in the general-purpose cell according to the embodiment, that is, thebasic configuration as the tray feeder 21, the relationship with thestage (processing stage) 31, an electrical construction inside the cell,operations of the cell in collaboration with the processing machine 70,etc., are basically the same as those in the first embodiment.

Construction of a production system using a plurality of general-purposecells exemplified in FIGS. 7 to 10, modifications thereof, and the likeare basically feasible with ease in the same or equivalent manner asthose in the first embodiment.

As described above, with a production system general-purpose cell and aproduction system using the general-purpose cell according to theembodiment, the same or equivalent effects as those in theaforementioned (1) to (8) in the first embodiment are obtained.

Among such effects, particularly the effect (4) is further promoted,resulting in obtainment of the following effects.

(9) The ceiling 11 r supported with columns 11 p is provided in an upperportion of the base unit 10 a, and the robot 90 is supported in the baseunit 10 a in such a manner that the robot 90 is hung from the ceiling 11r.

This allows the motion range of the robot 90 to cover a wide rangeincluding the whole area below the ceiling 11 r.

In particular, an area constituting the base unit 10 a is utilized moreeffectively.

(10) In particular, the robot 90 has the first and second arms 92 and 94having the same length that allows the first and second arms 92 and 94to have their individual circular motion areas and each pass theoverlapping positions.

A SCARA type robot is employed in which the first and second arms 92 and94 are turnable clockwise and counterclockwise by 225° with an attitudeof the arms overlapping each other taken as the original attitude.

This enables the motion range of the entire robot 90 to be basicallycircular and cover the entire area inside the circle with thecollaboration of the first and second arms 92 and 94.

That is, in the motion range of the robot 90 set from the inside to theoutside of the base unit 10 a, dead angles at least in the base unit 10a are eliminated with reliability.

For example, more smooth motions in operations of picking up parts froma parts tray can be expected.

(11) Thus, an area constituting the base unit 10 a is utilized moreeffectively, and a parts tray transported by the tray feeder 21constituting the parts supply unit 20 can be upsized as dead angles ofthe robot 90 in the same area are eliminated.

That is, the number of parts that can be supplied at one time to thegeneral-purpose cell 200 can be increased, and the frequency ofoperations required for supplying parts by the tray feeder 21constituting the parts supply unit 20 can be reduced.

Other Embodiments

Note that the foregoing embodiments may be practiced in the followingways.

-   -   Although the side wall 11 to support the robot 60 is provided        standing upright to the base unit 10 from the base portion side        of the parts supply unit 20 particularly in the foregoing first        embodiment, the side wall 11 may be provided standing upright at        a midpoint of the base unit 10 if it is expected that there is        room for space in the base unit 10.

In brief, the side wall 11 may be provided, in balance with the motionrange, to be separate from the processing area 30 so that the motionrange of the robot 60 reaches at least part of the processing area 30.

In this way, if the rail length of the tray feeder 21 constituting theparts supply unit 20 is reduced, the size of the general-purpose cell100 itself may be reduced.

-   -   On the other hand, in the foregoing second embodiment, the first        and second arms 92 and 94 constituting the robot 90 are set such        that they can turn from their original attitudes clockwise and        counterclockwise, that is, in the “±” direction at a turnable        angle of “225°”.

However, by setting the turnable angles to be “±180°” or more, the wholearea inside a circle exemplified in FIG. 12B can be covered such thatdead angles are eliminated with reliability.

The turnable angle of the first and second arms 92 and 94 is not limitedto be “±180°” or more, but may each be set to be less than “±180°” ifthe required motion range is secured.

-   -   In the foregoing second embodiment, regarding the tray feeder 21        constituting the parts supply unit 20 a, a cell configuration is        employed that allows parts that are supplied while being carried        on the parts tray to be transported through the base unit 10 a        to a lower portion of the processing area 30, that is, a        position lower than the stage 31, as in the first embodiment.

In the second embodiment, however, the robot 90 is supported in such amanner that it is hung from the ceiling 11 r, and therefore there isbasically no portion to block the movement of the parts tray.

Accordingly, the degree of freedom in arrangement of the tray feeder 21is, as a matter of course, maintained high.

The tray feeder 21, in this case, may be one that can transport theforegoing parts tray through the base unit 10 a to a vicinity of theprocessing area 30 a (stage 31).

That is, a step and the like need not to be provided between the region12 of a quadrangular planar shape and the stage 31 constituting theprocessing area 30 a in the base unit 10 a.

Even with this, operations of picking up appropriate parts by the robot90 and operations of transporting the picked-up parts to the processingarea 30 a by the robot 90 are carried out smoothly.

In addition, in the case of the second embodiment, the motion range ofthe robot 90 broadly covers the transportation area including the partstray to be transported to the base unit 10 a.

This therefore allows reduction of the frequency of operations requiredfor supplying parts by the tray feeder 21 by upsizing the parts trayitself.

-   -   Although a mechanism that has ball screws and nails threadably        engaged therewith and automatically transports a tray and the        like is employed as the tray feeder 21 constituting the parts        supply units 20 and 20 a or as the workpiece automatic        transportation units 131 and 132 in the foregoing embodiments,        the transportation mechanism is not limited to this and may be        configured arbitrarily.

As such a unit, for example, other mechanisms that electromagneticallyinduce and move transportation subjects may also be employed asappropriate.

-   -   Although the tray feeder 21 constituting the parts supply unit        20 or 20 a drives two rails 22 a and 22 b by the first and        second shuttle motors MSa and MSb in the foregoing embodiments,        both the rails 22 a and 22 b may be driven by one shuttle motor.

The tray feeder 21 may also include one rail.

-   -   Although the tray feeder 21 constituting the parts supply unit        20 or 20 a transports the parts tray Tr by driving two rails 22        a and 22 b together in the foregoing embodiments.

However, this is not restrictive.

If the rails 22 a and 22 b are individually driven to alternatelytransport the parts trays having such sizes that they do not interfereeach other by the respective rails 22 a and 22 b, supplying parts to thecells 100 and 200 can be performed smoothly.

-   -   Although an electrical connection is made through a        communication line as exemplified in FIG. 8 in configuring a        production system using a plurality of general-purpose cells in        the foregoing embodiments, the communication form is arbitrary        regardless of wire communication or radio communication.

An equivalent communication network may be established using either thecell 100 or the cell 200, intentionally without the central controller120.

-   -   Although the specific processing machine 70 is placed for the        processing area 30 or 30 a and processing of a workpiece is        performed by the processing machine 70 in the foregoing        embodiments, the uses of the processing area 30 or 30 a and the        robot 60 or 90 are arbitrary in each general-purpose cell.

For example, these processing area and robot may be utilized in thefollowing ways.

(A) Only a mechanism and the like for holding transported workpieces areprovided in a processing area, and a robot itself carries out alloperations including processing of workpieces.

That is, in this case, the robot carries out the following operations:

a. transporting a workpiece to the processing area;

b. picking up parts supplied through a parts supply unit;

c. integrating the picked-up parts into the workpiece;

d. processing in the above processing area the workpiece into which theparts have been integrated; and

e. delivering the workpiece processed in the processing area.

Additionally, in this case, the content of processing for the robot tocarry out needs to be set (programmed) for each cell in configuring aproduction system in a sequence of the cells mentioned above.

If the set content is registered into a storage device such as the database 122 (FIG. 8) in advance, for example, changes in line configurationcan be handled by updating the set content for each cell.

That is, the required general versatility is maintained in this case.

(B) An automatic tool changer that automatically replaces a hand (tool)of a robot with a new one is provided in the processing area, and therobot itself carries out all operations including automatic replacementof tools and processing of workpieces.

That is, in this case, the robot carries out the following operations:

a. picking up parts supplied through a parts supply unit;

b. integrating the picked-up parts into the workpiece;

c. processing in the above processing area the workpiece into which theparts have been integrated;

d. delivering the processed workpiece; and

e. automatic replacement of a robot hand, as needed, for the operationsa to d by means of the foregoing automatic tool changer.

Particularly in this case, automatic replacement of a robot hand, asneeded, by means of the automatic tool changer provided in theprocessing area is carried out as the operation of the above e togetherwith other operations, and therefore more kinds of operations can behandled.

In this case, when a production system is configured in a sequence ofthe above cells, the content of processing for the robot to carry outneeds to be set (programmed) for each cell.

However, the required general versatility as the cell is preferablymaintained by registering the set content into a storage device such asthe data base 122 (FIG. 8) in advance.

That is, in changing the line configuration, it can be handled byupdating the set content for each cell.

-   -   Although SCARA type robots are employed as the robots 60 and 90        in the foregoing embodiments, the type of the robot is arbitrary        particularly in the uses as the above (A) and (B).

Other types of robots such as one having a function like a “human hand”may be employed as appropriate.

-   -   Although examples in which processing areas 30 and 30 a are        integrally connected to the base units 10 and 10 a are taken in        the foregoing embodiments, the processing areas 30 and 30 a        constituting the general-purpose cells 100 and 200 may be        configured as separate, replaceable bodies extending outside the        base units 10 and 10 a, respectively.

In this case, the effect of suppressing transmittance of vibrationbetween the processing areas 30 and 30 a and the base unit 10 and 10 a,respectively, can be expected.

As a result, an inspection by an inspection device that is likely to beaffected by vibration can be preferably performed in the processingarea.

Further, in this case, arrangement of a cell configuration as in thegeneral-purpose cells 100C and 100E exemplified in FIG. 9 referencedabove is facilitated, and, in turn, the degree of freedom of a linelayout as illustrated in FIG. 9 is further increased.

That is, it is necessary for a production system general-purpose cellthat one general-purpose cell is constituted of a set of minimumelements such as a base unit, a parts supply unit, and a processing arearequired for processing of a workpiece as a cell for a productionsystem.

From this viewpoint, providing the aforementioned material supply area50 a and the material removal area 50 b are not essential for thegeneral-purpose cell.

For example, if a workpiece can be transferred between robots in thecells adjacent to each other, the material supply area 50 a and thematerial removal area 50 b may be not provided.

What is claimed is:
 1. A cell comprising: a robot; a processing stagethat periodically receives a workpiece placed thereon by the robot; anda caster enabling the cell to move; wherein the processing stage ismovable relative to the robot.
 2. The cell according to claim 1,comprising: a control device controlling the robot.
 3. The cellaccording to claim 2, comprising: a supply device supplying theworkpiece to the robot.
 4. The cell according to claim 3, comprising: abase having a planar area and movably supporting the robot on the planararea.
 5. The cell according to claim 4, wherein: the base, the supplydevice, and the processing stage are independently movable relative toone another.
 6. The cell according to claim 5, wherein the base, thesupply device, and the processing stage are configured to be mutuallyconnected to each other.